package com.villaday.idf.util;

/*
 *
 * float 和 double 只能用来做科学计算和工程计算。商业运算中我们要使用 BigDecimal。
 * */

import java.math.BigDecimal;

public class BigDecimalUtil {

    private BigDecimalUtil() {


    }

    public static BigDecimal add(double v1, double v2) {// v1 + v2
        BigDecimal b1 = new BigDecimal(Double.toString(v1));
        BigDecimal b2 = new BigDecimal(Double.toString(v2));
        return b1.add(b2);
    }

    public static BigDecimal sub(double v1, double v2) {
        BigDecimal b1 = new BigDecimal(Double.toString(v1));
        BigDecimal b2 = new BigDecimal(Double.toString(v2));
        return b1.subtract(b2);
    }

    public static BigDecimal mul(double v1, double v2) {
        BigDecimal b1 = new BigDecimal(Double.toString(v1));
        BigDecimal b2 = new BigDecimal(Double.toString(v2));
        return b1.multiply(b2);
    }

    public static BigDecimal div(double v1, double v2,int scale) {
        BigDecimal b1 = new BigDecimal(Double.toString(v1));
        BigDecimal b2 = new BigDecimal(Double.toString(v2));
        // 2 = 保留小数点后两位   ROUND_HALF_UP = 四舍五入
        return b1.divide(b2, scale, BigDecimal.ROUND_HALF_UP);// 应对除不尽的情况
    }
}
